1. Creativity and mental illness: Prevalence rates in writers and their first-degree relatives;Andreasen;American Journal of Psychiatry,1987
2. Creativity and mood disorders;Andreasen;Dialogues in Clinical Neuroscience,2008
3. Aristophanes bce The knights http://classics.mit.edu/Aristophanes/knights.pl.txt
4. A neuropsychological theory of positive affect and its influence on cognition;Ashby;Psychological Review,1999